XPS m1530 grey screen

This error may have been posted already, i have a friend's Dell XPS m1530 that was not booting into Vista, the vista loading bar came up for a couple seconds and then the screen went black, after about 5-8mins, a blue screen would come up giving an error ( which i cannot remember). I would then have to manual shut it down, I assumed that the windows was corrupt and proceeded to boot from a flash drive to install windows 7, the install started to load and then the screen display was glitchy, like those old genesis games that were dirty, anyways, i could not see anything besides the glitchy mouse, restarted and then the screen comes up grey with some darker lines between, i tried an external monitor but it just shows glitchy, i cannot make out to do anything on the screen, is this a display driver issue, if so why did it happen so suddenly? and how can i be fixed?

Could be a power supply issue, a failing hard drive, one memory module failing, or a video graphics card failing. Not likely a driver issue.
That XPS m1530 model has a very touchy motherboard which has a history of problems... failing memory sockets, etc. It also has heating problems with that cooling screen to the CPU fills up with lint, dust, dirt, and fiber... the resulting overheating seems to speed along the failure of various components. The power supply has performance issues if you have a powerfull video graphics card.
Give us the brand and the build date on the hard drive... and the model number of the video graphics card.
I am betting on a video card failure and the hard drive failing... if it is a Maxtor, Samsung, or Hitachi